Networked computers represent significant targets of opportunity for both recreational and malicious hackers, viruses, worms, scripted attacks, etc. Hacks and hackers are called different things and have different levels of sophistication, but in almost all cases successful hacks gain access to a computer through its network interface. This is particularly true when the network interface is coupled to the Internet. Computers supporting Internet Protocol (IP) and other IP network nodes, are identified by their IP address. Each network interface may support thousands of ports. To help manage security of the network interface, a firewall may be employed to process data arriving for individual ports. Some ports such as port 80, commonly used for HTTP protocol support, may be assigned or opened to allow traffic to pass through to a corresponding service, for example, running on a web server, that manages HTTP traffic. The firewall may close all other ports to restrict outside traffic from gaining access to connected devices on an internal network.
Internet protocol security (IPsec) allows the remote user or machine to be identified and is an additional mechanism for providing security to Internet traffic. A firewall may be programmed to require IPsec security on incoming connections. However, maintaining accurate connection information in a firewall can become tedious and prone to error. Detailed configuration knowledge may be required and the highest levels of protection may require frequent changes to the settings. For example, broad application level exceptions may be authorized because it is too difficult or time-consuming to program a narrower, more appropriate, exception. Furthermore, due to the difficulty of configuring such elaborate settings, firewall configuration is generally statically set, wherein exceptions are configured once and then left unaltered thereafter. This decreases the security of the machine by causing the firewall configuration to not accurately represent the precise security requirements of a machine at a given moment, but instead represent the least restrictive superset of the needed configuration at all times.